Difference between revisions of "Naming Objects"

From GeoGebra Manual
Jump to: navigation, search
Line 14: Line 14:
 
* If you don’t manually assign a name to an object, GeoGebra assigns the names of new objects in alphabetical order.
 
* If you don’t manually assign a name to an object, GeoGebra assigns the names of new objects in alphabetical order.
 
* You can create indices within the names of objects by using an underscore. For example A<sub>1</sub> is entered as <code>A_1</code> and s<sub>AB</sub> is entered as <code>s_{AB}</code>. }}
 
* You can create indices within the names of objects by using an underscore. For example A<sub>1</sub> is entered as <code>A_1</code> and s<sub>AB</sub> is entered as <code>s_{AB}</code>. }}
 +
 
==Reserved labels==
 
==Reserved labels==
There are a few labels you can't use for objects: x, y, z, xAxis, yAxis, zAxis.
+
There are a few labels you can't use for objects: x, y, z, xAxis, yAxis, zAxis.  
  
Once you create object dependent on imaginary unit ''i'' or Euler number ''e'', [[Free, Dependent and Auxiliary Objects|auxiliary]] object called ''i'' (resp. ''e'')  is created. From that moment you cannot use this label for other objects. On the other hand, if you define for instance ''e=3'', you will have to use special '''e''' character from the symbol list to get Euler number.
+
In the symbol list of the input bar, you will find special characters for the following constants:
 +
* π - the circle constant pi
 +
* ℯ - the Euler number, e.g. for the exponential function ℯ^x
 +
* ί - the imaginary unit, e.g. for complex numbers like z = 3 + ί
 +
When the variable names e resp. i are not used yet, they are automatically read as ℯ resp. ί for convenience.
  
 
See also [[Labels and Captions]].
 
See also [[Labels and Captions]].

Revision as of 14:02, 26 July 2011


You can assign a certain name to an object when you create it using the Input Bar:

  • Points: In GeoGebra, points are always named using upper case letters. Just type in the name (e. g., A, P) and an equal sign in front of the coordinates or commands.
Example: C = (2, 4), P = (1; 180°)
  • Vectors: In order to distinguish between points and vectors, vectors need to have a lower case name in GeoGebra. Again, type in the name (e. g., v, u) and an equal sign in front of the coordinates or commands.
Example: v = (1, 3), u = (3; 90°)
  • Lines, circles, and conic sections: These objects can be named by typing in the name and a colon in front of their equations or commands.
Example: g: y = x + 3, c: (x-1)^2 + (y – 2)^2 = 4, hyp: x^2 – y^2 = 2
  • Functions: You can name functions by typing, for example, f(x) = or g(x)= in front of the function’s equation or commands.
Example: h(x) = 2 x + 4, q(x) = x^2, trig(x) = sin(x)
Note:
  • If you don’t manually assign a name to an object, GeoGebra assigns the names of new objects in alphabetical order.
  • You can create indices within the names of objects by using an underscore. For example A1 is entered as A_1 and sAB is entered as s_{AB}.

Reserved labels

There are a few labels you can't use for objects: x, y, z, xAxis, yAxis, zAxis.

In the symbol list of the input bar, you will find special characters for the following constants:

  • π - the circle constant pi
  • ℯ - the Euler number, e.g. for the exponential function ℯ^x
  • ί - the imaginary unit, e.g. for complex numbers like z = 3 + ί

When the variable names e resp. i are not used yet, they are automatically read as ℯ resp. ί for convenience.

See also Labels and Captions.

© 2021 International GeoGebra Institute